#!/usr/bin/env python3
#
# Copyright (C) 2018 VyOS maintainers and contributors
#
# This program is free software; you can redistribute it and/or modify
# it under the terms of the GNU General Public License version 2 or later as
# published by the Free Software Foundation.
#
# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
# GNU General Public License for more details.
#
# You should have received a copy of the GNU General Public License
# along with this program.  If not, see <http://www.gnu.org/licenses/>.
#

import re
import sys

from vyos.configtree import ConfigTree


if len(sys.argv) < 2:
    print("Must specify file name!")
    sys.exit(1)

file_name = sys.argv[1]

with open(file_name, 'r') as f:
    config_file = f.read()

config = ConfigTree(config_file)

# Convert the old VRRP syntax to the new syntax

# The old approach was to put VRRP groups inside interfaces,
# as in "interfaces ethernet eth0 vrrp vrrp-group 10 ...".
# It was supported only under ethernet and bonding and their
# respective vif, vif-s, and vif-c subinterfaces

def get_vrrp_group(path):
    group = {"preempt": True, "rfc_compatibility": False, "disable": False}

    if config.exists(path + ["advertise-interval"]):
        group["advertise_interval"] = config.return_value(path + ["advertise-interval"])

    if config.exists(path + ["description"]):
        group["description"] = config.return_value(path + ["description"])

    if config.exists(path + ["disable"]):
        group["disable"] = True

    if config.exists(path + ["hello-source-address"]):
        group["hello_source"] = config.return_value(path + ["hello-source-address"])

    # 1.1.8 didn't have it, but earlier 1.2.0 did, we don't want to break
    # configs of early adopters!
    if config.exists(path + ["peer-address"]):
        group["peer_address"] = config.return_value(path + ["peer-address"])

    if config.exists(path + ["preempt"]):
        preempt = config.return_value(path + ["preempt"])
        if preempt == "false":
            group["preempt"] = False

    if config.exists(path + ["rfc3768-compatibility"]):
        group["rfc_compatibility"] = True

    if config.exists(path + ["preempt-delay"]):
        group["preempt_delay"] = config.return_value(path + ["preempt-delay"])

    if config.exists(path + ["priority"]):
        group["priority"] = config.return_value(path + ["priority"])

    if config.exists(path + ["sync-group"]):
        group["sync_group"] = config.return_value(path + ["sync-group"])

    if config.exists(path + ["authentication", "type"]):
        group["auth_type"] = config.return_value(path + ["authentication", "type"])

    if config.exists(path + ["authentication", "password"]):
        group["auth_password"] = config.return_value(path + ["authentication", "password"])

    if config.exists(path + ["virtual-address"]):
        group["virtual_addresses"] = config.return_values(path + ["virtual-address"])

    if config.exists(path + ["run-transition-scripts"]):
        if config.exists(path + ["run-transition-scripts", "master"]):
            group["master_script"] = config.return_value(path + ["run-transition-scripts", "master"])
        if config.exists(path + ["run-transition-scripts", "backup"]):
            group["backup_script"] = config.return_value(path + ["run-transition-scripts", "backup"])
        if config.exists(path + ["run-transition-scripts", "fault"]):
            group["fault_script"] = config.return_value(path + ["run-transition-scripts", "fault"])

    # Also not present in 1.1.8, but supported by earlier 1.2.0
    if config.exists(path + ["health-check"]):
        if config.exists(path + ["health-check", "interval"]):
            group["health_check_interval"] = config.return_value(path + ["health-check", "interval"])
        if config.exists(path + ["health-check", "failure-count"]):
            group["health_check_count"] = config.return_value(path + ["health-check", "failure-count"])
        if config.exists(path + ["health-check", "script"]):
            group["health_check_script"] = config.return_value(path + ["health-check", "script"])

    return group

# Since VRRP is all over the place, there's no way to just check a path and exit early
# if it doesn't exist, we have to walk all interfaces and collect VRRP settings from them.
# Only if no data is collected from any interface we can conclude that VRRP is not configured
# and exit.

groups = []
base_paths = []

if config.exists(["interfaces", "ethernet"]):
    base_paths.append("ethernet")
if config.exists(["interfaces", "bonding"]):
    base_paths.append("bonding")

for bp in base_paths:
    parent_path = ["interfaces", bp]

    parent_intfs = config.list_nodes(parent_path)

    for pi in parent_intfs:
        # Extract VRRP groups from the parent interface
        vg_path =[pi, "vrrp", "vrrp-group"]
        if config.exists(parent_path + vg_path):
            pgroups = config.list_nodes(parent_path + vg_path)
            for pg in pgroups:
                g = get_vrrp_group(parent_path + vg_path + [pg])
                g["interface"] = pi
                g["vrid"] = pg
                groups.append(g)

            # Delete the VRRP subtree
            # If left in place, configs will not load correctly
            config.delete(parent_path + [pi, "vrrp"])

        # Extract VRRP groups from 802.1q VLAN interfaces
        if config.exists(parent_path + [pi, "vif"]):
            vifs = config.list_nodes(parent_path + [pi, "vif"])
            for vif in vifs:
                vif_vg_path = [pi, "vif", vif, "vrrp", "vrrp-group"]
                if config.exists(parent_path + vif_vg_path):
                    vifgroups = config.list_nodes(parent_path + vif_vg_path)
                    for vif_group in vifgroups:
                        g = get_vrrp_group(parent_path + vif_vg_path + [vif_group])
                        g["interface"] = "{0}.{1}".format(pi, vif)
                        g["vrid"] = vif_group
                        groups.append(g)

                    config.delete(parent_path + [pi, "vif", vif, "vrrp"])

        # Extract VRRP groups from 802.3ad QinQ service VLAN interfaces
        if config.exists(parent_path + [pi, "vif-s"]):
            vif_ss = config.list_nodes(parent_path + [pi, "vif-s"])
            for vif_s in vif_ss:
                vifs_vg_path = [pi, "vif-s", vif_s, "vrrp", "vrrp-group"]
                if config.exists(parent_path + vifs_vg_path):
                    vifsgroups = config.list_nodes(parent_path + vifs_vg_path)
                    for vifs_group in vifsgroups:
                        g = get_vrrp_group(parent_path + vifs_vg_path + [vifs_group])
                        g["interface"] = "{0}.{1}".format(pi, vif_s)
                        g["vrid"] = vifs_group
                        groups.append(g)

                    config.delete(parent_path + [pi, "vif-s", vif_s, "vrrp"])

                # Extract VRRP groups from QinQ client VLAN interfaces nested in the vif-s
                if config.exists(parent_path + [pi, "vif-s", vif_s, "vif-c"]):
                    vif_cs = config.list_nodes(parent_path + [pi, "vif-s", vif_s, "vif-c"])
                    for vif_c in vif_cs:
                         vifc_vg_path = [pi, "vif-s", vif_s, "vif-c", vif_c, "vrrp", "vrrp-group"]
                         vifcgroups = config.list_nodes(parent_path + vifc_vg_path)
                         for vifc_group in vifcgroups:
                              g = get_vrrp_group(parent_path + vifc_vg_path + [vifc_group])
                              g["interface"] = "{0}.{1}.{2}".format(pi, vif_s, vif_c)
                              g["vrid"] = vifc_group
                              groups.append(g)

                         config.delete(parent_path + [pi, "vif-s", vif_s, "vif-c", vif_c, "vrrp"])

# If nothing was collected before this point, it means the config has no VRRP setup
if not groups:
    sys.exit(0)

# Otherwise, there is VRRP to convert
 
# Now convert the collected groups to the new syntax
base_group_path = ["high-availability", "vrrp", "group"]
sync_path = ["high-availability", "vrrp", "sync-group"]

for g in groups:
    group_name = "{0}-{1}".format(g["interface"], g["vrid"])
    group_path = base_group_path + [group_name]

    config.set(group_path + ["interface"], value=g["interface"])
    config.set(group_path + ["vrid"], value=g["vrid"])

    if "advertise_interval" in g:
        config.set(group_path + ["advertise-interval"], value=g["advertise_interval"])

    if "priority" in g:
        config.set(group_path + ["priority"], value=g["priority"])

    if not g["preempt"]:
        config.set(group_path + ["no-preempt"], value=None)

    if "preempt_delay" in g:
        config.set(group_path + ["preempt-delay"], value=g["preempt_delay"])

    if g["rfc_compatibility"]:
        config.set(group_path + ["rfc3768-compatibility"], value=None)

    if g["disable"]:
        config.set(group_path + ["disable"], value=None)

    if "hello_source" in g:
        config.set(group_path + ["hello-source-address"], value=g["hello_source"])

    if "peer_address" in g:
        config.set(group_path + ["peer-address"], value=g["peer_address"])

    if "auth_password" in g:
        config.set(group_path + ["authentication", "password"], value=g["auth_password"])
    if "auth_type" in g:
        config.set(group_path + ["authentication", "type"], value=g["auth_type"])

    if "master_script" in g:
        config.set(group_path + ["transition-script", "master"], value=g["master_script"])
    if "backup_script" in g:
        config.set(group_path + ["transition-script", "backup"], value=g["backup_script"])
    if "fault_script" in g:
        config.set(group_path + ["transition-script", "fault"], value=g["fault_script"])

    if "health_check_interval" in g:
        config.set(group_path + ["health-check", "interval"], value=g["health_check_interval"])
    if "health_check_count" in g:
        config.set(group_path + ["health-check", "failure-count"], value=g["health_check_count"])
    if "health_check_script" in g:
        config.set(group_path + ["health-check", "script"], value=g["health_check_script"])

    # Not that it should ever be absent...
    if "virtual_addresses" in g:
        # The new CLI disallows addresses without prefix length
        # Pre-rewrite configs didn't support IPv6 VRRP, but handle it anyway
        for va in g["virtual_addresses"]:
            if not re.search(r'/', va):
                if re.search(r':', va):
                    va = "{0}/128".format(va)
                else:
                    va = "{0}/32".format(va)
            config.set(group_path + ["virtual-address"], value=va, replace=False)

    # Sync group
    if "sync_group" in g:
        config.set(sync_path + [g["sync_group"], "member"], value=group_name, replace=False)

# Set the tag flag
config.set_tag(base_group_path)
if config.exists(sync_path):
    config.set_tag(sync_path)

try:
    with open(file_name, 'w') as f:
        f.write(config.to_string())
except OSError as e:
    print("Failed to save the modified config: {}".format(e))
    sys.exit(1)
